A system determining user's context (conditions) based on information obtained from a sensor to provide service corresponding to the user's context, is known.
As an example of such system, non-patent document 1 sets forth a system providing guidance information by using user's location information obtained from GPS (Global Positioning System) as user's context information.
Further, non-patent document 2 discloses technology of generating user's context information based on a plurality of sensor information to execute an application corresponding to the generated context information.    [Non-Patent Document 1] Keith Cheverst, Developing a Context-aware Electronic Tourist Guide: Some Issues and Experiences, Proceedings of CHI 2000, Netherlands, April 2000, pp 17-24.    [Non-Patent Document 2] Anind K. Dey, The Context Toolkit: Aiding the Development of Context-Aware Applications, [online], (searched on May 12, 2005), Internet: <URL: http://www.cc.gatech.edu/fce/contexttoolkit/pubs/SEWPC00.pdf>